This relates in general to security ventilating systems, more particularly as such systems are applied to residential and business premises having laterally rolling or sliding doors and/or windows.
In the present-day state of society, breaking and entering into residential and business premises is all too common. Accordingly, it is necessary to augment the conventional types of locks, which skilled burglers can easily circumvent, additional security is especially needed in the case of horizontally sliding glass doors or windows of the types employed in so many modern houses, apartments and stores. During warm weather, it is desirable to open such doors or windows for ventilation; and even if a screen door is interposed in the opening, it can be readily and quietly cut and opened. Moreover, when the doors or windows are closed, the intruder breaks or cuts the glass, and reaches through to unlock the door by manipulating the handle from the inside, which is located in a conventional position visible from the outside; or he may use a tool to force such doors or windows up to unlock, unlatch or force conventional locks to release, actually removing the door or window from its track.
Numerous security systems have been devised in accordance with the prior art, such as various types of grills, window guards, and screens; but none of them is suitable for use with sliding glass doors or windows which are opened to different positions. Moreover, they are either too expensive or cumbersome to install, or the locks are readily identifiable from the outside and easily removed by a skilled burgler having simple tools; or they are too difficult to open to enable escape from an indoor fire. Furthermore, some of the systems of the prior art are too massive and heavy for the purposes contemplated for the security ventilating system of the present invention and especially for adaptation to existing doors or window frames.
Accordingly, it is the principal object of the present invention to provide an improved security system applicable to an arrangement of sliding doors comprising either a single sliding door or window or a plurality of fixed and sliding doors or windows of various conventional arrangements and of a variety of heights and widths.
A more particular object of the invention is to provide a system which is simple, positive and inexpensive to install for current, or existing old installations and buildings.
A further object of the invention is to provide a security system which can be locked in place when the sliding doors or windows are opened to each of a series of different positions for the purposes of variable degrees of ventilation.
Still another object of the invention is to provide a security system which is not visible to potential intruders from the outside of the doors or windows, and which is not, therefore, readily located or removed.
Another object of the invention is to fully cope with the potential intruder's attempt to unlock, by either raising or sliding, the sliding door or window.
These and other objects are attained in a security system in accordance with the present invention which is particularly applicable to an arrangement of sliding doors or windows. Such a system comprises means adapted to be interposed into the space between the door or window jamb casing and the door or window frame when one of the group of sliding doors or windows is partially opened for ventilation; and which provides additional locking means when the doors or windows are tightly closed. This arrangement comprises a light-weight, high-strength metal lift-out grill which is constructed to be fitted into the void created when one of the sliding doors or windows is opened, the length and width of the grill varying in accordance with the size of the door or window frame. The left-hand vertical bar of the lift-out grill is secured in an auxiliary channel which is fastened along the inside edge of the left-hand door or window frame. Either the right-hand vertical bar of the grill, or alternatively, one of the series of parallel vertical bars thereof, fastens into a series of vertically aligned channels set on the inside edge of the door or window frame. Also, a horizontally directed lug fastened to each of the vertical bars is constructed to be interposed below the door or window handle to further secure the grill in place. Lastly, a strong rough-faced pin or stud is connected to a short chain or cord inside of the door frame; and said pin or stud is constructed to key into one of a series of fairly snug holes perforating the inner edge of the upper door or window corresponding to each of a series of door or window opening positions. This pin or stud passes through the upper frames of the overlapping sliding doors or windows, but does not pass through the outer edge of the door or window frame channel, so that it cannot be seen from the outside.
Another security feature designed to prevent the movable door from being lifted out of its bottom track by a screw driver or crow bar is a square metal bar or tube mounted in the top trough above the sliding door and extended beyond the maximum security opening of the door so that its mounting bolt is never available to a potential intruder. Another security feature is to have the inner flanges of the track actually extend a short distance into recesses in the lower rails of the inner and outer doors, so that the sliding doors slide along these rails. This is not, per se, a novel feature; but in common with the other features described, tends to make a burgler-proof system.
For convenience of description, the security system of the present invention is described hereinafter with reference to an arrangement consisting of one fixed door and one sliding door which is adapted to slide laterally along the inner face of the fixed door so that in completely open position, it is colinear with the fixed door. It will be understood, however, that with slight modification, the security system of the present invention may be applied to numerous variations of this arrangement. For example, the fixed and sliding doors may be reversed in direction. The arrangement may comprise a fixed door at the center with sliding doors at its opposite ends which are adapted to slide toward one another, along the inner face of the fixed door, to open. Alternatively, one sliding door may be adapted to slide along the outer face of the fixed door, and the other sliding door may be adapted to slide along the inner face of the fixed door. In still another arrangement with the fixed door in the center, the sliding doors, in open positions, may be stored in recesses in the wall, moving toward the fixed door to close. Other arrangements will occur to those skilled in the art.
These and other objects, features and advantages will be apparent to those skilled in the art when studying the specification hereinafter with reference to the attached drawings.